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Author Topic:   FORD ? Please help
T/10
Dirt Full Roller

Total posts: 71
posted April 20, 2005 07:45 PM  
I have a ford 351w with world product SR. heads, dome pistons comp.is 225 cranking pressure. The problem is that it keeps blowing the head gasket between # 6&7 cylinders. When it blows it will burn a groove in the block and head. I have done this 2 times and have been able to get the heads repaired. But I am afraid to try it again. I might not be able to repair them again. I run methonal, timing is at 36 Deg. Spark plugs are AR132, they don't show to be lean,they have a nice tan color. Can anyone help solve my problem? Thanks;.

ford5
Dirt Forum Champ
Total posts: 711
posted April 21, 2005 05:40 AM  
You may look into the possibilty of having poor grade (cheap alcohol) sounds a little far fetched, maybe, but I have had that happen to me before and the common denominator was the alky. Is your distributor locked? Seen alot of guys with unlocked distributors think that their timing was set at 36 max, but when revved higher the timing was in fact actually going higher and this would cause the same thing to occur. You definanetly have a timing\detonation issue here.

rpm20
Dirt Freak

Total posts: 338
posted April 21, 2005 05:51 AM  
look for timing issues, you are getting detonation. had the same thing happen a few years back on a 350 on gas, it would get hot, detonate and burn the gasket, head and cylinder walls and make junk of my motor.

use a std , good timing light with no advance and set timing so you can see what it is at 4000-5000 rpms.

dluna
Dirt Freak

Total posts: 334
posted April 21, 2005 07:35 AM  
At the beginning of last year, we used some alcohol left over from the prior year. I am pretty certain that is what caused 2 of our motors to burn between 3 and 5...I will no longer save fuel over the winter.

T/10
Dirt Full Roller

Total posts: 71
posted April 21, 2005 06:18 PM  
My distributor is not locked..... I have all MSD Ign. I have the lightest springs in the distributor that it came with. If you think this could be my problem, I will definitely lock it down. Do you think that 36 deg. is to much total timing or should I also lower it to say 31 to 32? Thanks.

oldfordmod
Dirt Full Roller

Total posts: 46
posted April 21, 2005 06:40 PM  
I don't know anything about the world heads but, the N-351 heads I run make peak power at 24 degrees total timming (13.5 CR). I would check with them about best total timming. Good luck, blown gaskets **** .

Dirt-Tracker
Dirt Maniac

Total posts: 182
posted April 22, 2005 05:04 PM  
I always run 36Degrees with my SR heads on my 347 with good luck. Make sure your at total 36 at around 3000-3500.

Gene
Dirt Freak

Total posts: 396
posted April 22, 2005 05:18 PM  
Have you checked for a vacuum leak ? A rule of thumb is a leak in the carb, gasket, or spacer will have 2 cyls (usually next to each other) run lean. It could be a loose pipe plug fitting in the intake also. You have one of those problems that can drive ya nuts and out of racing. If you do find the cause please let us know.

HEAVY DUTY
Dirt Full Roller

Total posts: 36
posted April 23, 2005 10:47 PM  
we dynoed our 375 ford with trick flow heads today at 34 degrees and at 28 degrees.28 degrees picked up 15 hp on top,and 10 to 20 lbs torque all the way thru.never got to try less than 28.

T/10
Dirt Full Roller

Total posts: 71
posted April 24, 2005 06:40 PM  
Thanks everyone for your input. I got the engine back in this weekend and everything went ok. I locked down the dist. set timing at 34 deg. It was a very dry slick track. Did not use hardly any motor at all, it might be a different story on a heavy track. I will let every one know if it is still ok in another 3 or 4 weeks. Thanks again.

dirtslinger66
Dirt Maniac

Total posts: 200
posted April 24, 2005 06:46 PM  
I had this problem a few years ago and it came down to a bad msd box. I melted the pistons and block 3 times before we found it.

T/10
Dirt Full Roller

Total posts: 71
posted April 25, 2005 04:39 AM  
How did you find it? I have no idea how you would check the MSD box.

tee1up6134
Dirt Full Roller

Total posts: 32
posted April 25, 2005 07:36 AM  
I know this is off the subject a little, but I need you ford guys opinion. Any of you ever have problems with cracking a block I have a 347 with 580 hp and cracked 3 main bolts and then outside of block, reputable engine builder said that this has happened before and I should use a dart block or similar because ford blocks arent very strong. Any help

oldfordmod
Dirt Full Roller

Total posts: 46
posted April 25, 2005 08:14 AM  
The engine builder is correct. Its not a matter of "if it will break" but "when" with a stroker crank. The block only is only about 130 lbs, no meat round the main webs. A slightly less expensive solution might be the 302 sportsman block from Ford, about 140 lbs and very thick main webs. Costs around 850 bucks. I just bought one and I am going to use it for a 347.

tee1up6134
Dirt Full Roller

Total posts: 32
posted April 25, 2005 10:25 AM  
Thanks for the reply oldford mod. Thats what we went with instead of the dart. Hopefully it will work out.

dirtslinger66
Dirt Maniac

Total posts: 200
posted April 25, 2005 04:30 PM  
The only way I know of is to send it to msd and have them check it out

Dman
Dirt Freak

Total posts: 270
posted April 26, 2005 08:01 AM  
A good friend of mine does a lot of Ford HP engine building and says on the dyno he has found that Fords run best at 28 degrees or less.It has something to do with combustion chamber shape and burn speed.I was told anything more than 28 with compression will detonate on the dyno. Hope this helps. Engine troubles can drive a guy to buy a boat and go fishin!

foxracin11
Dirt Full Roller

Total posts: 26
posted May 01, 2005 08:17 AM  
hey guys i think you are right we have put our ford windsors on the dyno one has the n heads and the other has the world heads and one has the pro heads and all liked the timing to be around 28 degrees the first motor we built didnot dyno and popped three head gaskets because we were trying to much timing 32- 34 i believe havent had a problem since

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